It needs more then an oil change.

The service ligts come on at regular intervals. The exact
interval can be programmed into it. Typically every 6 months/6K miles
or 12 month/12K miles. You should check the owers manual for a list
of service needed at your current milage. As an example, every
50K miles you need a new timing belt for the 93 engine. At 30K
intervals would be plugs, air filter, etc. A lot of people think
Volvos are tanks that can be driven and forgotton. The opposite is
true -- they need to be well maintained to keep them reliable and
running (a broken timing belt will cost $3K in engine damage so
this stuff must be maintained).